Micellar solutions of thin film spreading agents comprising polyepoxide condensates or resinous polyalkylene oxide adducts and polyether polyols

ABSTRACT

The invention provides a homogeneous, micellar solution of a water-insoluble thin film spreading agent comprising polyepoxide condensates of resinous polyalkylene oxide adducts and polyether polyols comprising: (a) from between about 5% and about 75% by weight of said polyepoxide condensate; (b) from between about 2% and about 30% by weight of a hydrotropic agent; (c) from between about 2% and about 30% by weight of an amphipathic agent; and (d) from between about 15% and about 90% by weight of water.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a new and improved micellar solution of a thinfilm spreading agent comprising polyepoxide condensates of resinouspolyalkylene oxide adducts and polyether polyols which are particularlyuseful for breaking or preventing petroleum emulsions. Morespecifically, the invention relates to a composition in which waterreplaces all or a substantial part of the organic solvents formerlyrequired for preparation of liquid solutions of this interfaciallyactive compound.

2. Description of the Prior Art

One of the principal uses of the present composition is in the breakingof petroleum emulsions to permit the separation thereof into two bulkphases. Much of the crude petroleum oil produced throughout the world isaccompanied by some water or brine which originates in or adjacent tothe geological formation from which the oil is produced. The amount ofaqueous phase accompanying the oil may vary from a trace to a very largepercentage of the total fluid produced. Due to the natural occurrence inmost petroleum of oil-soluble or dispersible emulsifying agents, much ofthe aqueous phase produced with oil is emulsified therein, formingstable water-in-oil emulsions.

The literature contains numerous reference to such emulsions, theproblems resulting from their occurrence, and the methods employed tobreak them and separate salable petroleum. See, for example, "TheTechnology of Resolving Petroleum Emulsions" by L. T. Monson and R. W.Stenzel, p. 535 et seq in Colloid Chemistry Vol VI, Ed. by JeromeAlexander, Rheinhold Publishing Corp., New York (1946) and "InterfacialFilms Affecting the Stability of Petroleum Emulsions" by Chas. M. Blair,Jr. in Chemistry and Industry (London), p. 538 et seq (1960).

Early demulsifiers used to resolve petroleum emulsions werewater-soluble soaps, Twitchell reagents, and sulfonated glycerides.These products were readily compounded with water to form easilypumpable liquids and were conveniently applied by pumping into flowlines at the well head or by washing down the casing annulus with waterto commingle with well fluids prior to their flow to the surface. Theseproducts, however, were effective only at relatively high concentrationsand their use added substantially to the cost of production.

Some time ago, it was discovered that certain lightly sulfonated oils,acetylated caster oils and various polyesters, all of which wereinsoluble in water but soluble in alcohols and aromatic hydrocarbons,were much more effective in breaking emulsions. Accordingly, essentiallyall commercial demulsifier development has led to production of agentswhich are insoluble in both water and petroleum oils and have otherproperties to be described below which cause them to spread at oil-waterinterfaces to form very thin, mobile films which displace anyemulsifying agent present in the oil to allow coalescence of dispersedwater droplets. Generally, such interfacially active compounds andhereafter referred to as Thin Film Spreading Agents, or "TFSA's". In thepast, these have had to be compounded with and dissolved in alcohols orhighly aromatic hydrocarbon solvents in order to produce readily appliedliquid compositions. A wide variety of such compositions are required totreat the many different emulsions encountered throughout the world.

While present TFSA compositions are highly effective, being, perhaps, upto fifty to a hundred times more effective per unit volume than theoriginal water-soluble demulsifiers, they suffer serious practicaldeficiencies because of their solubility characteristics. For example,alcohols and the aromatic hydrocarbons, which are required forpreparation of liquid, pumpable compositions, are quite expensive, todayapproaching in cost that of the active demulsifier ingredient itself.Further, such solvents are flammable and thus create safety problems andentail more expense in shipping, storing and use. The low flash pointflammability can be improved by using high boiling aromatic solvents,but these are increasingly rare, expensive and dangerous from thestandpoint of carcinogenicity and dermatological effects.

Still further, present demulsifiers cannot generally be used in asubterranean oil or gas well, injection well, or the like, since theycannot be washed down with either water (or brine) or a portion of theproduced oil, and, being viscous liquids which are required in verysmall amounts, they cannot be reliably and continuously deliveredseveral thousand feet down at the fluid level in a typical well withoutuse of elaborate and expensive delivery means.

Other applications of TFSA compositions would be facilitated if theywere readily soluble or dispersible in water. For example, much heavy,viscous oil is produced in the United States by steam injectionprocedures. Typically, wet steam is injected into the oil producingstrata for several weeks in order to heat the oil, lower its viscosityand increase reservoir energy. Steam injection is then stopped and oilis flowed or pumped from the bore hole which was used for steaminjection. Much of the water resulting from condensation of the steam isalso produced with the oil in emulsified form. Since emulsions are moreviscous than the external phase at the same temperature, and thus createincreased resistance to flow, productivity of the steamed wells can beimproved by injecting a water-soluble demulsifier into the wet steamduring the steam injection period to prevent emulsion formation. See,for example, U.S. Pat. No. 3,396,792, dated Apr. 1, 1966, to F. D.Muggee. At present, the requirement of water solubility seriously limitsthe choice of demulsifiers for use in steam or water injection to therelatively inefficient compositions.

As disclosed in my co-pending applications, Ser. No. 045,479, filed June4, 1979 and entitled "Method Of Recovering Petroleum From A SubterraneanReservoir Incorporating A Polyether Polyol", Ser. No. 45,478, filed June4, 1979, now U.S. Pat. No. 4,260,019, and entitled "Method of RecoveringPetroleum From A Subterranean Reservoir Incorporating ResinousPolyalkylene Oxide Adducts", Ser. No. 45,360, filed June 4, 1979, nowU.S. Pat. No. 4,216,828, and entitled "Method Of Recovering PetroleumFrom A Subterranean Reservoir Incorporating An Acylated PolyetherPolyol", and Ser. No. 45,470, filed June 4, 1979, and entitled "Methodof Recovering Petroleum From A Subterranean Reservoir IncorporatingPolyepoxide Condensates Of Resinous Polyalkylene Oxide Adducts AndPolyether Polyols", TFSA's are useful in processes for enhanced recoveryof petroleum. Used in such processes involving displacement of residualoil by aqueous solutions, polymer solutions and other aqueous systems,these agents act to increase the amount of oil recovered. Such actionpossibly arises from their ability to further water wetting of reservoirrock, lessen the viscosity of the oil-water interfacial layer andpromote coalescence of dispersed droplets of either water or oil in theother phase.

By use of the present aqueous micellar solutions, the introduction ofTFSA into aqueous displacement of flooding fluids is greatlyfacilitated. In addition, the present micellar solutions, per se, or incombination with other components, can be used as the flooding agent oras a pretreating bank or slug ahead of other aqueous fluids.

Other applications for the present TFSA micellar solutions include theiruse as flocculation aids for finely ground hematite and magnetite oresduring the desliming step of ore beneficiation, as additives forimproving the oil removal and detergent action of cleaning compositionsand detergents designed for use on polar materials, for the improvementof solvent extraction processes such as those used in extraction ofantibiotic products from aqueous fermentation broths with organicsolvents, for the improvement of efficiency and phase separation in thepurification and concentration of metals by solvent extraction withorganic solutions of metal complex-forming agents, and as assistants toimprove the wetting and dying of natural and synthetic fibers and forother processes normally involving the interface between surfaces ofdiffering polarity or wetting characteristics.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide aqueous, liquidcompositions of these TFSA's having new and useful characteristics whichallow production of: petroleum emulsion breakers and emulsion preventingcompositions free or relatively free of highly flammable andenvironmentally objectionable aromatic hydrocarbons; compositions havinga comparatively low cost; compositions which are soluble or dispersiblein water and which, therefore, can often be applied by more effectivemethods than can existing products; compositions which can be used inenhanced recovery operations such as steam flooding and aqueous mediumflooding where present products cannot be readily applied; andcompositions which can be compounded with water-soluble reagents ofother types, such as corrosion inhibitors, wetting agents, scaleinhibitors, biocides, acids, etc., to provide multipurpose compounds foruse in solving many oil well completion, production, transportation andrefining problems.

In accordance with the present invention, these aims are accomplished bymeans of amphipathic agents which are capable of forming micellarsolutions and which by this mechanism or other undefined actions,combined with those of a second essential component which will bereferred to as a hydrotropic agent, are able to form homogeneous aqueoussolutions containing a relatively wide range of concentrations of TFSA.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The TFSA compositions of the present invention can be broadlycategorized by the following general characteristics:

1. Solubility in water and isooctane at about 25° C. is less than about1% by volume;

2. Solubility parameter at about 25° C. is in the range of from betweenabout 6.8 to about 8.5, with a majority in the range of from between 7.0and about 7.9; and

3. Spread at the interface between white, refined mineral oil anddistilled water to form films having a calculated thickness no greaterthan about 20 Angstroms at a spreading pressure of about 16 dynes percm.

TFSA compositions having these properties are generally organic polymersor semi-polymers having molecular weights ranging from about 2,000 toabout 100,000 and having structures containing a multiplicity ofdistributed hydrophilic and hydrophopic moieties arranged in linear orplanar arrays which make them surface active and lead to theiradsorption at oil-water interfaces to form very thin films.

Unlike most commonly encountered surface-active compounds, the presentTFSA appears to be incapable of forming a micelle in either oil orwater. The distributed and alternating occurrence of polar and nonpolaror hydrophilic and hydrophobic groups in the molecule apparentlyprevents the kind of organization required for micelle formation andthus impairs dispersion or solution in either water or low polarityorganic solvents.

The TFSA's useful in the present invention have the previously recitedproperties:

1. The solubility in water and in isooctane at about 25° C. is less thanabout 1% by volume.

Solubility tests may be run by placing a 1 ml sample (or the weight ofsolid product calculated to have a volume of 1 ml) in a graduatedcylinder of the type which may be closed with a ground glass stopper.Thereafter place 99 ml of water in the cylinder, close, place in a 25°C. water bath until thermal equilibrium is reached, and remove from thebath and shake vigorously for one hour. Return the sample to the bathfor five minutes and then repeat the shaking procedure. Finally, returnthe sample to the bath and allow it to stand quietly for one hour. Thecylinder contents should be carefully examined and any cloudiness oropacity of the liquid phase or the appearance of any sediment orundissolved material in the cylinder noted, thus indicating that thesample satisfied the requirement for insolubility in water.

Isooctane solubility is determined similarly by substituting thishydrocarbon for the water used above.

2. The Solubility Parameter (S.P.) at about 25° C. is from between about6.9 and about 8.5, inclusive.

Methods of determination of solubility parameter are disclosed in JoelH. Hildebrand, "The Solubility of Nonelectrolytes", Third Edition, pgs.425 et seq. However, a simplified procedure, sufficiently accurate forqualification of a useful TFSA composition may be utilized. Componentsof a give solubility parameter are generally insoluble in hydrocarbon(non-hydrogen-bonding) solvents having a lower solubility parameter thanthemselves. Therefore, the present composition should be soluble in ahydrocarbon solvent of a solubility parameter of about 6.8. Since thesolubility parameter of mixtures of solvents is an additive function ofvolume percentage of components in the mixture, test solutions of thedesired solubility parameters may be easily prepared by blending, forexample, benzene (S.P. 9.15) and isooctane (S.P. 6.85) orperfluoro-n-heptane (S.P. 5.7).

A mixture of about 72 parts of benzene with about 28 parts of isooctanewill provide a solvent having a solubility parameter of about 8.5 atroom temperature (about 25° C.). Perfluoro-n-heptane has a solubilityparameter of about 5.7 at 25° C., so a mixture of 68 parts of thissolvent with 32 parts of benzene provides a solvent with a solubilityparameter of about 6.8, or isooctane of a solubility parameter 6.85 maybe used.

When 5 ml of the TFSA are mixed with 95 ml of an 8.5 solubilityparameter solvent at room temperature, a clear solution should result.When 5 ml of TFSA is mixed with a 6.85 solubility parameter solvent, acloudy mixture or one showing phase separation should result. Solventmixtures have a solubility parameter between about 7.0 and about 7.9 maybe prepared as described above and utilized in a similar test procedure.

In interpreting the solubility parameter and other tests, it should berecognized that the TFSA consists not of a single material or compoundbut a cogeneric mixture of products containing a range of products ofmolecular weights distributed around the average molecular weight andeven containing small amount of the starting compounds employed in thesynthesis. As a result, in running solubility and solubility parametertests, very slight appearances of cloudiness or lack of absolute clarityshould not be interpreted as a pass or a failure to pass the criteria.The intent of the test is to ensure that the bulk of the cogenericmixture, i.e., 75% or more, meets the requirement. When the results isin doubt, the solubility test may be run in centrifuge tubes allowingsubsequent rapid phase separation by centrifuging, after which theseparated non-solvent phase can be removed, any solvent contained in itcan be evaporated, and the actual weight or volume of separated phasecan be determined.

3. The TFSA should spread at the interface between distilled water andrefined mineral oil to form films with thickness no greater than about20 Angstroms (0.0020 micrometer) at a spreading pressure of about 16dynes per cm (0.016 Newton per meter).

Suitable methods of determining film pressure are disclosed in N. K.Adam, "Physics and Chemistry of Surfaces", Third Edition, OxfordUniversity Press, London, 1941, pgs. 20 et seq, and C. M. Blair, Jr.,"Interfacial Films Affecting The Stability of Petroleum Emulsions",Chemistry and Industry (London), 1960, pgs. 538 et seq. Film thicknessis calculated on the assumption that all of the TFSA remains on the areaof interface between oil and water on which the product or its solutionin a volatile solvent has been placed. Since spreading pressure isnumerically equal to the change in interfacial tension resulting fromspreading of a film, it is conveniently determined by making interfacialtension measurements before and after adding a known amount of TFSA toan interface of known area.

Alternatively, one may utilize an interfacial film balance of theLangmuir type such as that described by J. H. Brooks and B. A. Pethica,Transactions of the Faraday Society (1964), p. 20 et seq, or othermethods which have been qualified for such interfacial spreadingpressure determinations.

In determining the interfacial spreading pressure of the TFSA products,I prefer to use as the oil phase a fairly available and reproducible oilsuch as a clear, refined mineral oil. Such oils are derived frompetroleum and have been treated with sulfuric acid and other agents toremove nonhydrocarbon and aromatic constituents. Typical of such oils is"Nujol", distributed by Plough, Inc. This oil ranges in density fromabout 0.85 and 0.89 and usually has a solubility parameter between about6.9 and about 7.5. Numerous similar oils of greater or smaller densityand viscosity are commonly available from chemical supply houses andpharmacies.

Other essentially aliphatic or naphthenic hydrocarbons of low volatilityare equally usable and will yield similar values of spreading pressure.Suitable hydrocarbon oils appear in commercial trade as refined "whiteoils", "textile lubricants", "paraffin oil", and the like. Frequently,they may contain very small quantities of alpha-tocopherol (Vitamin E)or similar antioxidants which are oil-soluble and do not interfere withthe spreading measurements.

While the existence of micelles and of oily or aqueous micellarsolutions have been known for some time (see, e.g., "Surface Activity",Moilliet, Collie and Black, D. Van Nostrand & Co., New York (1961)) andare probably involved in many operations involving detergency whereeither oily (nonpolar) or earthy (highly polar) soil particles are to beremoved, their utility in cooperation with hydrotropic agent for thepresent purposes is an unexpected and unpredictable discovery.

In U.S. Pat. No. 2,356,205, issued Aug. 22, 1944, to Chas. M. Blair, Jr.& Sears Lehman, Jr., a wide variety of micellar solutions designed todissolve petroleum oils, bitumen, wax, and other relatively nonpolarcompounds are described for purposes of cleaning oil formation faces andfor effecting enhanced recovery of petroleum by solution thereof. Atthis early date, however, the use of micellar principles was notcontemplated for the preparation of solutions of the reltively highmolecular weight demulsifiers.

However, some of the principles disclosed in the above patent, omittingthe main objective therein of dissolving relatively large amounts ofhydrocarbons, chlorinated hydrocarbons, and the like, are applicable topreparation of the present compositions.

The four necessary components of the micellar solutions of TFSA are:

1. A micelle-forming amphipathic agent. Such may be anionic, cationic,or nonionic and, if anionic or cationic, may be either in salt form oras the free acid or free base or mixtures thereof.

2. A hydrotropic agent. This is a small to medium molecular weightsemi-polar compound containing oxygen, nitrogen or sulfur and capable offorming hydrogen bonds. It is believed that such agents cooperate insome manner with the amphipathic agent to form clear or opalescent,stable compositions.

3. Water.

4. TFSA, having the properties recited above.

In addition to these components, the micellar solutions may contain, butare not required to contain, salts, hydrocarbons, or small amounts ofother inorganic or organic material. Such constituents may beimpurities, solvents, or by-products of syntheses used in forming thehydrotropic agent, or may be additions found useful in forming thecomposition of this invention. As an example of the latter, smallamounts of inorganic salts such as NaCl, Na₂ SO₄, KNO₃, CaCl₂, and thelike, are sometimes helpful in promoting homogeneity with a minimum ofamphipathic and hydrotropic agents. They may also yield compositions oflower freezing point, a property useful when the composition is employedin cold climates. Similarly, ethylene glycol, methanol, ethanol, aceticacid, or similar organic compounds may be incorporated into thecompositions to improve physical properties such as freezing point,viscosity, and density, or to improve stability.

As stated above, the micelle-forming amphipathic agents which may beused in preparing the aqueous solutions herein contemplated may beeither cation-active, anion-active, or of the nonelectrolytic type.Amphipathic agents generally have present at least one radicalcontaining about 10 or more carbon atoms and not more than about 64carbon atoms per molecule. This is true of the amphipathic agentsemployed in the present invention as a component of the vehicle orsolvent or dispersant employed in the present compositions. Thehydrophobic portions of these agents may be aliphatic, alicyclic,alkylalicyclic, aromatic, arylalkyl, or alkylaromatic. The preferredtype of agents are those in which the molecule contains a long,uninterrupted carbon chain containing from 10 to 22 carbon atoms inlength. Examples of suitable anion-active amphipathic agents include thecommon soaps, as well as materials such as sodium cetyl sulfate,ammonium lauryl sulfonate, ammonium di-isopropyl naphthalene sulfonate,sodium oleyl glyceryl sulfate, mahogany and green sulfonates frompetroleum or petroleum fractions or extracts, sodium stearamidoethylsulfonate, dodecylbenzene sulfonate, dioctyl sodium sulfosuccinate,sodium naphthenate, and the like. Other suitable sulfonates aredisclosed and taught in U.S. Pat. No. 2,278,171, issued Feb. 17, 1942,to De Groote and Keiser.

Suitable cation-active compounds include cetyl pyridinium chloride,stearamidoethyl pyridinium chloride, trimethyl-heptadecyl ammoniumchloride, dimethyl-pentadecyl sulfonium bromide, octadecylamine acetate,and 2-heptadecyl-3-diethylene diaminoimidazoline diacetate.

Suitable nonelectrolytic amphipathic agents include the oleic acid esterof nonaethylene glycol, the steric acid ester of polyglycerol,oxyethylated alkylphenols, and long chain alcohol ethers of polyethyleneglycols.

It is of course, well known that amphipathic compounds are readily andcommercially available, or can be readily prepared to exhibit thecharacteristics of more than one of the above mentioned types. Suchcompounds are disclosed in U.S. Pat. No. 2,262,743, dated Nov. 11, 1941,to De Groote, Keiser and Blair. For convenience, in such instances wherea surface-active material may show the characteristics of more than oneof the above described types, it is understood that it may be classifiedunder either or both types.

The mutual solvent or hydrotropic agents of the solution utilized in thepresent invention are characterizable as compounds of a hydrophobichydrocarbon residue of comparatively low molecular weight combined witha hydrophilic group of low molecular weight and are free fromsurface-active properties. The hydrophobic residue may contain from 2 to12 carbon atoms and may be alkyl, alicyclic, aromatic, or alkylsubstituted alicyclic or aromatic, or may be the hydrocarbon portion ofa heterocyclic or hydrocarbon substituted heterocyclic group. Thehydrocarbon residue may have branched or normal chain structure, but nobranch may have a length of more than 7 carbon atoms from the point ofattachment to the hydrophilic residue, counting a benzene or cyclohexylgroup as being equivalent in length to an aliphatic chain of threecarbon atoms. Where the hydrocarbon residue consists of not more than 4carbon atoms, structures of the normal primary alkyl type are preferred.Where the residue is made up of more than four carbon atoms, thenstructures of secondary and tertiary types are also good where thesecond and third branches may be methyl or ethyl groups.

This hydrophobic hydrocarbon residue is combined either directly orindirectly with a hydrophilic group of one of the following groups:

(a) A hydroxyl group which may be alcoholic, phenolic, or carboxylic;

(b) An aldehyde group;

(c) A carboxy amide group;

(d) An amine salt group;

(e) An amine group; and

(f) An alkali phenolate group.

By "indirectedly combined with one of these groups" is meant that thehydrocarbon residue is combined as by etherification, esterification, oramidification, or the like, with another organic residue which containsnot more than four carbon atoms and also one or more of the hydrophilicgroups named above, provided that after said combination, at least oneof the hydrophile groups remains free. Specific examples illustratingthis class of compounds are: Ethyl alcohol, n-amyl alcohol,alphaterphineol, p-cresol, cyclohexanol, n-butyraldehyde, benzaldehyde,n-butyric acid, glycol mono-butyrate, propyl lactate, mono n-butyl aminehydrochloride, n-propionamid, ethylene glycol mono n-butyl aminehydrochloride, n-propionamid, ethylene glycol mono n-butyl ether,pyridine, methylated pyridine, piperidine, or methylated piperidines.

The solubilizer (mutual solvent or hydrotropic compound above described)is essentially a semi-polar liquid in the sense that any liquid whosepolar character is no greater than that of ethyl alcohol and which showsat least some tendency to dissolve in water, or have water dissolved init, is properly designated as semi-polar.

The solubilizer or semi-polar liquid indicated may be illustrated by theformula X--Z, in which X is a radical having 2 to 12 carbon atoms, andwhich may be alkyl, alicyclic, aromatic, alkylalicyclic, alkylaryl,arylalkyl, or alicyclicalkyl in nature, and may, furthermore, includeheterocyclic compounds and substituted heterocyclic compounds. There isthe added limitation that the longest carbon atom chain must be lessthan eight carbon atoms, and that, in such characterization, cycliccarbon atoms must be counted as one-half. Z represents:

    --OH; ##STR1##

    --COOH; or --OMe

where U and V are hydrogen or a hydrocarbon substituent and Me is analkalie metal; ##STR2## if X is a cyclic teritary amine nucleus;

    >NH

if X is a cyclic secondary amine nucleus.

The semi-polar liquid also may be indicated by the following formula:X--Y--R--(Z)_(n). Here X and Z have their previous significance, R is

    --CH.sub.2 --,--C.sub.2 H.sub.4 --,--C.sub.3 H.sub.5 ═; --C.sub.3 H.sub.6 -- or --C.sub.2 H.sub.4 --O--C.sub.2 H.sub.4 --

and n is either one or two as the choice of R demands. Y is one of thefollowing: ##STR3##

    --O--; --S--.

In general, these hydrotropic agents are liquids having dielectricconstant values between about 6 and about 26, and have at least onepolar group containing one or more atoms of oxygen, and/or nitrogen. Itis significant, perhaps, that all of the solubilizers are of types knownto be able to form hydrogen bonds.

The choice of solubilizer or common solvent and its proportion in themixture depends somewhat upon the amphipathic agent used, the amount andkind of TFSA used, and the proportion of water used, and is bestdetermined by preparing experimental mixtures on a small scale.

In some cases, it is desirable to include in the solution small amountsof acid, alkali, or inorganic salts, as it has been found that thepresence of these electrolytes often gives solutions having greaterstability and a wider range of miscibility with water and organicmaterial. Excess acid, when used, will usually be in solutionscontaining a cation-active or nonelectrolytic wetting agent, but notexclusively so. Excess alkali, when used, will usually be in a solutioncontaining anion-active wetting agents, but, again, not exclusively.

The polyether polyol or TFSA utilized in this invention is generally anorganic polymer or semi-polymer with an average molecular weight aboveabout 800 and below about 30,000 and has a structure which will alloworientation on polar surfaces with much or most of the elements of themolecule in a thin plane. To be effectively adsorbed at oil-water oroil-rock interfaces and subsequently to be desorbed at water-rockinterfaces, the TFSA must generally contain constituents which give it ahighly distributed hydrophile and hydrophobe character, and without suchconcentrations of either hydrophilic or hydrophobic groups as to producewater solubility or oil solubility, in the ordinary macroscopic sense.The TFSA also appears to differ from formerly used surfactants in thatthe effects on oil-water interfacial tensions as a function ofconcentration are limited. While spreading efficiently at suchinterfaces to form thin films with spreading pressures up to about 35 to40 dynes per cm, addition or larger amounts of TFSA have relativelylittle effect on interfacial tension. Also, the present TFSA constituentof the micellar solution in contrast to formerly used surfactants, hasrelatively little or no tendency to stabilize either oil-in-water orwater-in-oil emulsions when present in normal use amounts.

Usually the TFSA constituents applicable to the practice of theinvention are organic molecules containing carbon, hydrogen and oxygen,although in some instances they may also contain sulfur, nitrogen,silicon, chlorine, phosphorous or other elements. Small amounts ofinorganic material such as alkalies, acids or salts may appear in thecompositions as neutralizing agents, catalyst residues or otherwise. Thecritical requirements for the TFSA compositions are not so muchcompositional as structural and physical. They must be made up ofhydrophilic (polar) moieties, usually ones capable of forming hydrogenbonds, such as hydroxyl, carbonyl, ester, ether, sulfonium, amino,ammonium, phospho or similar hydrogen bonding groups, connected by or tohydrophobic groups, such as alkylene, alkyl, cycloaklyl, aryl, arylene,aralkyl, polyalkylene, polyalkylyne, combinations of such groups andsuch groups containing relatively non-polar substituents, such ashydrocarbon, chlorine, fluorine and the like. Sometimes the hydrophobicmoieties are larger and contain more atoms than the polar groups in themolecule, having a minimum of two carbon atoms in each group and up toas many as 36 carbon atoms, although the actual ratio of sizes dependsgreatly on the structure of the hydrophilic moiety. Most commonly, thehydrophobic groups will contain 14 to 22 carbon atoms and will havelinear or sheet-like conformations allowing for relatively flatorientation on surfaces.

Polar moieties other than hydrogen bonding ones are not excluded fromthese compositions and, indeed, may be deliberately included in somestructures to improve adsorption and interfacial spreading tendencies.For example, quaternary ammonium groups, while incapable of forminghydrogen bonds, can improve spreading and interfacial adsorption in someapplications by way of their highly ionized form which imparts cationiccharacter to the molecules in which they occur and, via coulombicrepulsion effects, can improve spreading in a film.

Generally, the TFSA constituents will contain at least two each of therequired hydrophilic (polar) and hydrophobic moieties per molecule andcommonly will contain many more of each. The effective products,however, must have the three properties described above.

While, as pointed out above, the effective TFSA may be derived from awide variety of chemical reactants and may contain numerous differentgroups or moieties, I have found that particularly effect products arethose which are described as a polyepoxide condensate of at least oneof: (1) a polyalkylene oxide adduct of a fusible, water-insolubleorganic aromatic hydrocarbon solvent-soluble synthetic resin, whereinsaid resin has from between about 4 to about 15 phenolic groups and isan alkyl or cycloaliphatic substituted phenol-aldehyde condensate of anortho- or para-substituted phenol and an aldehyde, said condensate resinbeing thereafter further condensed with an alkylene oxide containingless than about five carbon atoms in an amount equal to at least onemole of alkylene oxide per phenolic moiety of said resin; and (2) apolyether polyol having the formula: ##STR4## wherein: A is an alkyleneoxide groups, --C_(i) H_(2i) O--;

O is oxygen;

i is a positive integer from 2 to about 10;

j is a positive integer no greater than about 100;

k is a positive integer no greater than about 100;

N is nitrogen;

R¹ is one of hydrogen, a monovalent hydrocarbon group containing lessthan about C₁₁, or [A_(L) H];

L is a positive integer no greater than about 100;

R is a hydrocarbon moiety of a polyol, a primary or secondary amine, aprimary or secondary polyamine, a primary or secondary amine alcohol, orhydrogen; and

m+n is no greater than about 4 when R is other than hydrogen and one ofm and n is zero and the other is unity when R is hydrogen. Thesepolyepoxide condensates must conform to the physical property parametersset forth above.

The polyalkylene oxide adducts are broadly described in U.S. Pat. No.2,499,365, entitled "Chemical Manufacture", dated Mar. 7, 1950, toDeGroote, et al. These compositions also include materials wherein lessthan one or two alkylene oxide units may be reacted with each reactivestructural group of the starting resin.

The most common resin is an alkyl or cycloaliphatic substitutedphenol-aldehyde resin prepared by condensing an ortho- orpara-substituted phenol with an aldehyde, most commonly withformaldehyde or a formaldehyde progenitor such as paraformaldehyde ortrioxane, under mildly alkaline or acidic conditions to form a fusibleand xylene-soluble polymer of low or moderate molecular weight and whichtypically will contain from between about 4 to about 12 phenolic groups.This resin is then condensed, usually with an alkaline catalyst, with analkylene oxide or a mixture of alkylene oxides.

Alkylene oxides suitable for use in preparing the compositions used inthe present process include ethylene oxide, propylene oxide, butyleneoxide, 2-3-epoxy-2-methyl butane, trimethylene oxide, tetrahydrofuran,glycidol, and similar oxides containing less than about 10 carbon atoms.Because of their reactivity and relatively low cost, the preferredalkylene oxides for preparing effective TFSA's are the 1,2-alkyleneoxides (oxiranes) exemplified by ethylene oxide, propylene oxide andbutylene oxide. In the preparation of many TFSA's, more than onealkylene oxide may be employed either as mixtures of oxides orsequentially to form block additions of individual alkylene oxidegroups.

To be suitable for use in the present process, addition and condensationof oxide must not be carried to the point of producing water-solubleproducts. Where ethylene oxide alone is condensed with the resin, theamount added preferably will be between one and five moles per phenolicmoiety in the resin. The actual amount will vary with the size of thealkyl or cycloalkylene group attached to the phenol ring as well as,apparently, with the composition and properties of the oil, aqueousphase and rock formation encountered in the method.

Where propylene or butylene oxides or mixtures of one or both of thesewith ethylene oxide are condensed with the phenolic resin intermediate,generally a greater amount of such oxides may be reacted without leadingto extremely polar, water-insoluble products. In contrast, the amount ofepichlorohydrin or glycerol chlorohydrin which can be condensed withoutproducing agents not meeting the solubility and interfacial spreadingcriteria defined above is usually somewhat lower.

On a solvent-free weight basis, the amount of alkylene oxide or mixtureof oxides condensed with the resin will fall within the range of aboutone part oxides to about 10 parts of resin and up to from between about1-to-5 and about 3-to-1. The final product should contain at least aboutone mole of alkylene oxides per phenolic moiety of the resin.

Compositions incorporated within the scope of the formula set forthabove for the polyether polyol contain an average of about 11/2 or morehydroxyl groups per molecule and are generally composed of a cogenericmixture of products obtained by condensing alkylene oxides with smallermolecules containing two or more reactive hydrogens as part of hydroxylor amino groups.

Representative of these compositions is polypropylene glycol, having anaverage molecular weight of about 1,200, to which about 20% by weight ofethylene oxide has been added. Such a polyether glycol is theoreticallyobtainable by condensing about 20 moles of propylene oxide with aboutone mole of water, followed by addition of about six moles of ethyleneoxide. Alternatively, one may condense about 20 moles of propylene oxidewith a previously prepared polyethylene glycol of about 240 averagemolecular weight.

Other suitable dihydric alcohols may be obtained by condensing alkyleneoxides or mixtures of oxides or in successive steps (blocks) withdifunctional (with respect to oxide addition) compounds, such asethylene glycol, methyl amine, propylene glycol, hexamethylene glycol,ethyl ethanolamine, analine, resorcinol, hydroquinone and the like.

Trihydric ether alcohols may be prepared by condensation of ethylene,propylene or butylene oxides with, for example, glycerin, ammonia,triethanolamine, diethanolamine, ethyl ethylene diamine or similarsmaller molecules containing three hydrogens capable of reacting withalkylene oxides. Similarly, polyether alcohols with a multiplicity ofhydroxyl groups may be obtained by condensing alkylene oxides withmultireactive starting compounds, such as pentaerythritol, glycerol,N-monobutyl ethylene diamine, trishydroxymethylaminomethane, ethylenediamine, diethylenetriamine, diglycerol, hexamethylene diamine,decylamine and cyclohexylamine. DeGroote, in U.S. Pat. No. 2,679,511,describes a number of amino derived polyols which he subsequentlyesterfies. Product 15-200, manufactured and sold by the Dow ChemicalCompany, and derived by oxyalkylation of glycerol with a mixture ofethylene and propylene oxides, is an example of a commercially availablepolyol of the kind contemplated herein.

Generally, these compositions will have average molecular weights of15,000 or less and will be derived from reactive hydrogen compoundshaving 18 or fewer carbon atoms and 10 or fewer reactive hydrogens.

Other general descriptions of suitable polyether polyols coming withinthe scope of the structure detailed above, along with methods forcarrying out the actual manufacturing steps, are disclosed in "HighPolymers, Vol XIII, Polyethers," edited by N. G. Gaylord, John Wiley &Sons, New York, 1963.

Suitable polyepoxide for condensation with the compounds set forth aboveinclude, particularly, the diglycidyl ether ofdihydroxyphenyl-methylmethane and the lower polymers thereof, which maybe formed as cogeneric mixtures and which have the general formula:##STR5## wherein n is zero of a positive integer or less than about 6.

Other polyepoxides containing two or more oxirane or epoxy groups, suchas diisobutenyl dioxide, polyepoxypolyglycerols, epoxidized linseed oil,epoxidized polybutadiene or the like, may also be employed.

The compositions suitable for practicing the present invention areprepared by reacting formaldehyde or a substance which breaks down toformaldehyde under the reaction conditions, e.g., paraformaldehyde andtrioxane, and a difunctional, with respect to reaction withformaldehyde, alkyl phenol, often a crude mixture of alkyl phenols foreconomic reasons, by heating the reactants between about 100° and about125° C. in the presence of a small amount of an acid catalyst such assulfamic acid or muriatic acid or, alternatively, in the presence of analkaline catalyst such as sodium hydroxide or sodium methylate and,preferably, under substantially anhydrous conditions, excepting thewater produced during the reaction. The aqueous distillate which beginsto form is collected and removed from the reaction mixture. Afterseveral hours of heating at temperatures slightly above the boilingpoint of water, the mass becomes viscous and is permitted to cool toabout 100°-105° C. At this point, an aromatic hydrocarbon fraction suchas xylene may be added, and heating is resumed. Further aqueousdistillate begins to form, and heating is continued for an additionalnumber of hours until at least about one mole of aqueous distillate permole of the formaldehyde has been distilled off. Xylene or otherhydrocarbon which may be distilled with the water is returned to thereaction mass. The temperature at the end of the reaction reaches about180°-250° C. The product is permitted to cool to yield thephenol-formaldehyde condensation product in the aromatic solvent.

The molecular weight of these intermediate condensation products cannotbe ascertained with certainty, but it is estimated that the resinsemployed herein should contain from between about 4 to about 15,preferably from about 4 to about 6, phenolic nuclei per resin molecule.The solubility of the condensation product in hydrocarbon solvent wouldindicate that the resin is a linear or sheet-like polymer, thusdistinguishing it from the more common phenol-formaldehyde resins of theinsoluble crosslinked type.

Having prepared the intermediate phenol-formaldehyde products, the nextstep is the oxyalkylation of the condensation products with alkyleneoxide. This is achieved by mixing the intermediate phenol-formaldehydecondensation product as is or contained in the aromatic solvent with asmall amount of a suitable catalyst, usually potassium hydroxide orsodium methylate, in an autoclave. The condensation product is heatedabove 100° C., and ethylene oxide, propylene oxide, butylene oxide ormixtures of two or all three of these oxides, either as a mixture or bysequential addition of first either one or another of the oxides ischarged into the autoclave until the pressure is in the vicinity of75-100 psi.

The reaction mixture is gradually heated until an exothermic reactionbegins. The external heating is then removed, and alkylene oxide oroxide mixture is added at such a rate that the temperature is maintainedbetween about 130°-160° C. in a pressure range of 30-100 psi. After allof the alkylene oxide has been added, the temperature is maintained foran additional 10 to 20 minutes to assure substantially complete reactionof the alkylene oxide. The resulting product is the alkylene oxideadduct of an alkyl phenol-formaldehyde condensation product, in whichthe weight ratio of the oxide to the condensation product (on asolvent-free basis) is between about 1-to-10 and about 10-to-1,preferably between about 1-to-5 and about 3-to-1, and containing atleast about one mole of alkylene oxide per phenolic moiety of the resin.

As to the limits of the various constituents of the micellar solutionscontaining TFSA, the following will serve as a guide, the percentagesbeing by weight:

    ______________________________________                                                         Percent                                                      ______________________________________                                        TFSA Constituents  about 5 to about 75                                        Hydrotropic Agent  about 2 to about 30                                        Amphipathic Agent  about 2 to about 30                                        Water              about 15 to about 90                                       ______________________________________                                    

Although the exact function of the electrolytes previously referred tois not completely understood, the effect, in part, may be due to theability to bind water, i.e., to become hydrated. This suggests thatcertain other materials which are highly hydrophile in character andclearly differentiated from the classes of non-polar solvents andsemi-polar solubilizers may be the functional equivalent of anelectrolyte. Substances of this class which ordinarily do not dissociateinclude glycerol, ethylene glycol, diglycerol, sugar, glucose, sorbitol,mannitol, and the like.

Also, as stated above, these solutions may contain other organicconstituents such as hydrocarbons. These frequently are used as thinningagents, azetropic distillation aids or reflux temperature controllers inthe manufacture of the TFSA constituent and may be left therein when thepresent micellar solutions are prepared. To the extent that suchcompounds are present they appear to compete somewhat with the TFSAconstituent for micelle space, thus limiting, to some extent, themaximum amount of TFSA constituent which can be brought into homogeneoussolution.

Selection of an effective TFSA composition for a given petroleumemulsion and determination of the amount required is usually made byso-called "bottle tests", conducted, in a typical situation, as follows:

A sample of fresh emulsion is obtained and 100 ml portions are pouredinto each of several 180 ml screw top prescription or similar graduatedbottles. Dilute solutions (1% or 2%) of various TFSA constituents areprepared in isopropyl alcohol. By means of a graduated pipette, a smallvolume of a TFSA solution is added to a bottle. A similar volume of eachcomposition is added to other bottles containing emulsion. The bottlesare then closed and transferred to a water bath held at the sametemperature as that employed in the field treating plant. After reachingthis temperature, the bottles are shaken briskly for several minutes.

After the shaking period, the bottles are placed upright in the waterbath and allowed to stand quietly. Periodically, the volume of theseparated water layer is recorded along with observations on thesharpness of the oil-water interface, appearance of the oil and clarityof the water phase.

After the standing period, which may range from 30 minutes to severalhours, depending upon the temperature, the viscosity of the emulsion andthe amount of TFSA compositions used, small samples of the oil areremoved by pipette or syringe and centrifuged to determine the amount offree and emulsified water left in the oil. The pipette or syringe usedto remove the test samples should be fitted through a stopper or otherdevice which acts as a position guide to insure that all bottles aresampled at the same fluid level.

The combined information on residual water and emulsion, speed of thewater separation and interface appearance provides the basis forselection of the generally most effective TFSA constituent. Where noneof the results are satisfactory, the tests should be repeated usinghigher concentrations of TFSA constituents and, conversely, where allresults are good and similar, the tests should be repeated at lowerconcentrations until good discrimination is possible.

In practicing the process for resolving petroleum emulsions of thewater-in-oil type with the present micellar solution, such solution isbrought into contact with or caused to act upon the emulsion to betreated, in any of the various methods or apparatus now generally usedto resolve or break petroleum emulsions with a chemical reagent, theabove procedure being used alone or in combination with otherdemulsifying procedure, such as the electrical dehydration process.

One type of procedure is to accumulate a volume of emulsified oil in atank and conduct a batch treatment of demulsification procedure torecover clean oil. In this procedure, the emulsion is admixed with themicellar TFSA solution, for example, by agitating the tank of emulsionand slowly dripping the micellar TFSA solution into the emulsion. Insome cases, mixing is achieved by heating the emulsion while dripping inthe micellar TFSA solution, depending upon the convection currents inthe emulsion to produce satisfactory admixture. In a third modificationof this type of treatment, a circulating pump withdraws emulsion from,e.g., the bottom of the tank and reintroduces it into the top of thetank, the micellar TFSA solution being added, for example, at thesuction side of said circulating pump.

In a second type of treating procedure, the micellar TFSA solution isintroduced into the well fluids at the wellhead, or at some pointbetween the wellhead and the final oil storage tank, by means of anadjustable proportioning mechanism or proportioning pump. Ordinarily,the flow of fluids through the subsequent lines and fittings suffices toproduce the desired degree of mixing of micellar TFSA solution andemulsion, although, in some instances, additional mixing devices may beintroduced into the flow system. In this general procedure, the systemmay include various mechanical devices for withdrawing free water,separating entrained water, or accomplishing quiescent settling of thechemically treated emulsion. Heating devices may likewise beincorporated in any of the treating procedures described herein.

A third type of application (down-the-hole) of micellar TFSA solution toemulsion is to introduce the micellar solution either periodically orcontinuously in diluted form into the well and to allow it to come tothe surface with the well fluids, and then to flow thechemical-containing emulsion through any desirable surface equipment,such as employed in the other treating procedures. This particular typeof application is especially useful when the micellar solution is usedin connection with acidification of calcareous oil-bearing strata,especially if dissolved in the acid employed for acidification.

In all cases, it will be apparent from the foregoing description, thebroad process consists simply in introducing a relatively smallproportion of micellar TFSA solution into a relatively large proportionof emulsion, admixing the chemical and emulsion either through naturalflow, or through special apparatus, with or without the application ofheat, and allowing the mixture to stand quiescent until the undesirablewater content of the emulsion separates and settles from the mass.

Besides their utility from breaking petroleum emulsions, the presentmicellar TFSA solutions, as mentioned earlier, may be used to preventemulsion formation in steam flooding, in secondary waterflooding, inacidizing of oil-producing formations, and the like.

Petroleum oils, even after demulsifications, may contain substantialamounts of inorganic salts, either in solid form or as small remainingbrine droplets. For this reason, most petroleum oils are desalted priorto refining. The desalting step is effected by adding and mixing withthe oil a few volume percentages of fresh water to contact the brine andsalt. In the absence of demulsifier, such added water would also becomeemulsified without effecting its washing action. The present micellarsolutions may be added to the fresh water to prevent its emulsificationand to aid in phase separation and removal of salt by the desaltingprocess. Alternatively, if desired, they may be added to the oil phaseas are present aromatic solvent compositions.

Most petroleum oil, along with its accompanying brines and gases, iscorrosive to steel and other metallic structures with which it comes incontact. Well tubing, casing, flow lines, separators and lease tanks areoften seriously attacked by well fluids, especially where acidic gasessuch as H₂ S or CO₂ are produced with the liquids, but also in systemsfree of such gases.

It has been known for some time, and as exemplified in U.S. Pat. No.2,466,517, issued Apr. 5, 1949, to Chas. M. Blair and Wm. F. Gross, thatsuch corrosive attack of crude oil fluids can be mitigated or preventedby addition to the fluids of small amounts or organic inhibitors.Effective inhibitors compositions for this use are usually semi-polar,surface active compounds containing a nonpolar hydrocarbon moietyattached to one or more polar groups containing nitrogen, oxygen orsulfur or combinations of such elements. Generally these inhibitors ortheir salts are soluble in oil and/or water (brine) and frequentlyappear to be able to form micelles in one or both of these phases.Typical inhbitors include amines such as octyl amine, dodecyl amine,dioctodecyl amine, butyl naphthyl amine, dicyclohexyl amine, benzyldimethyldodecyl ammonium chloride, hexadecylaminopropyl amine,declyoxypropyl amine, mixed amines prepared by hydrogenation of nitrilederivatives of tall oil fatty acids, soya acid esters of monoethanolamine, 2-undecyl, 1-amino ethyl imidazoline and a wide variety ofcationic nitrogen compounds of semi-polar character. Also effective insome applications are nonyl succinic acid, diocylnaphthalene sulfonicacid, trimeric and dimeric fatty acids, propargyl alcohol,mercaptobenzothiozole, 2, 4, 6-trimethyl-1, 3, 5-trithiaane,hexadecyldimethyl benzimidazolium bromide,2-thiobutyl-N-tetrodecylpyridinium chloride,tetrahydronaphthylthiomorpholine, and the like.

In contrast to the TFSA, corrosion inhibits appear to function byforming on the metal surface strongly adherent, thick, closely packedfilms which prevent or lessen contact of corrosive fluids and gases withthe metal and interfere with ionic and electron transfer reactionsinvolved in the corrosion process.

Corrosion inhibitors are quite commonly introduced down the casingannulus of oil wells where they commingle with the well fluids beforetheir travel up the well tubing and thus can effectively preventcorrosion of well equipment. Where corrosive attack occurs at thesurface, the inhibitor may be introduced at or near the well head,allowing it to adsorb on the flow lines and surface equipment to insureprotection.

Addition of inhibitor at either downhole or surface locations may becombined conveniently with demulsifier addition since the latter is alsofrequently introduced in one of these locations.

Inhibitors such as those mentioned above, may generally be incorporatedinto the TFSA micellar solutions, replacing a portion of or in additionto the TFSA constituent. Also, since many of these inhibitors arethemselves micelle-forming amphipathic agents, they may be included inthe micellar solution as such, replacing other amphipathic agents whichmight be otherwise utilized. Combining the micellar solution withcorrosion inhibitor permits more economic chemical treatment by reducinginventory to one compound, requiring only one chemical injection systemrather than two and lessening the labor and supervision required.

Still another important effect of using the micellar solution of TFSAand corrosion inhibitor results from the prevention of emulsification bythe inhibitor. Frequently, it has been found that inhibitor in theamount required for effective protection causes the formation of veryrefractive emulsions of water and hydrocarbon, especially in systemscontaining light, normally nonemulsifying hydrocarbons such asdistillate, casing head gasoline, kerosene, diesel fuel and variousrefinery fractions. Inhibitors are commonly used in refinery systemswhere emulsification is highly objectionable and where the compositionscould be designed to include an effective emulsion preventative micellarsolution of TFSA.

Inhibitor use may range from a few to several hundred parts per millionbased on the oil to be treated, depending upon the severity ofcorrosion. For a given oil field or group of wells, tests wil normallybe run to determine the requirement for micellar solution of TFSA andfor inhibitor and a composition incorporating these components inapproximately the desired ratio will be prepared. In some instances, therequirement for micellar solution of TFSA in the best concentration mayresult in use of corrosion inhibitor, employed as micelle-former, insome excess over that required for inhibition. This will not affect theutility of the micellar solution and will provide a comfortable excessof inhibition which can be helpful during the periods when highercorrosivity may be encountered.

Examples of micellar solutions employing TFSA with inhibitor in waterdispersible, micellar solutions are given below.

Selection of the proper corrosion inhibitor for a given system or oil isusually made by conducting laboratory tests under conditions simulatingthose encountered in the well or flowline. Such tests are exemplified bythat described in Item No. 1K155, "Proposed Standardized LaboratoryProcedure for Screening Corrosion Inhibitors for Oil and Gas Wells",published by the National Association of Corrosion Engineers, Houston,Tex.

EXAMPLES OF THIN FILM SPREADING AGENTS EXAMPLE IA RESINOUS POLYALKYLENEOXIDE ADDUCT PRECURSER

Reference is made to U.S. Pat. No. 2,499,365, to M. De Groote, issuedMar. 7, 1950, which describes generally the manufacture of demulsifiersby the oxyalkylation of fusible, organic solvent-soluble, alkylphenolresins. The procedure of Example 74a of this patent was followed toprepare a fusible, xylene soluble p-dodecylphenol resin in xylenesolution. The acid catalyst was neutralized, water was removed byazetropic distillation of some zylene and 0.5% by weight of sodiummethylate catalyst was added. Using the procedure of Example 1b of thecited patent, 25% by weight of ethylene oxide, based on the final batchweight, was added and reacted with the resin.

EXAMPLE IB FINAL PRODUCT PREPARATION

Reference is made to U.S. Pat. No. 3,383,325 to V. L. Seale, et al,dated May 14, 1968, which described demulsifiers prepared by condensingpolyether polyols and oxyalkylated alkylphenol resins with diglycidylethers of bis-phenol compounds.

One hundred parts of the product of Example 1, in co-pending Ser. No.082,349, filed Oct. 5, 1979, entitled "Micellar Solutions of Thin FilmSpreading Agents Comprising A Polyether Polyol", was reacted with 15parts of the diglycidyl ether of bis-phenol A, followed by reacting with80 parts of the product of Example IA, above, all in accordance with theprocedure of the Seale, et al, patent, Example D8. Addition of the final300 parts of SO₂ extract was omitted. This product meets the threecriteria for thin film spreading agent.

EXAMPLE II

The procedure employed in Example 44a of U.S. Pat. No. 2,499,365, to M.DeGroote, issued Mar. 7, 1950, was followed to produce an alkalinecatalyzed, fusible, xylene-soluble p-tertiary amylphenol resin.

Using the procedure described under Example IA, above, 1,000 lbs. ofthis resin solution was reacted with 1,000 lbs of a mixture of 150 lbs.of butylene oxide, 250 lbs. of propylene oxide and 600 lbs. of ethyleneoxide.

After completion of the oxide addition, the temperature was adjusted to140° C. and 70 lbs of diemthyl, diglycidyl hydantoin dissolved in 250lbs. of xylene was slowly introduced with rapid stirring. Aftercompletion of the epoxy hydantoin addition, stirring and heating at 140°C. was continued until the batch viscosity at 100° C. was between 1,500and 2,000 centipoises.

EXAMPLE III

The procedure of Example I was followed except that condensation withthe oxylalkylated phenolic resin and final addition of SO₂ extract wereboth deleted.

The product was an effective demulsifier meeting the criteria describedabove, therefor. This product was also found to improve the percentageof oil recovery when used as an additive to water used in experimentalsecondary waterflooding tests.

EXAMPLE IV

The procedure of Example I is followed, except that 12 parts ofCiba-Geigy Resin XB2818, an alkylated dihydantoin containing threeepoxide groups, was substituted for the 15 parts of diglycidyl etherused in Example I. Reaction was continued until the product exhibited aviscosity of about 1,500 centipoises at 100° C. The final product metthe three criteria for TFSA.

EXAMPLE V

Into a 500 gal. stainless steel autoclave equipped with stirrer, steamjacket, cooling coils and appropriate inlet and outlet lines wasintroduced 1,000 lbs. of commerical polypropylene glycol with averagemolecular weight of 4,000. Sixteen pounds of a 50% aqueous solution ofpotassium hydroxide was then added to the glycol. Steam was admitted tothe jacket and the contents were stirred while the temperature wasbrought to about 125° C.

A slow stream of nitrogen was blown through the vessel contents duringthe heating period to effect removal of water. Nitrogen sparging wasstopped when a sample of the glycol showed a water content below 0.1%.

At this point, commercial epoxidized soyabean oil containing an averageof three epoxy groups per glyceride molecule was added at a slowcontinuous rate while the temperature was increased to 145° C. Additionwas stopped after 90 lbs. of epoxidized soyabean oil had beenintroduced. Stirring and heating at 145° C. was continued until thereaction mixture had a viscosity within the range of 1,200 to 1,400centipoises when measured at 100° C.

EXAMPLES OF MICELLAR SOLUTIONS INCORPORATING TFSA's EXAMPLE A

    ______________________________________                                                           Wt. %                                                      ______________________________________                                        Product of Example II                                                                              38                                                       Isopropanol          16                                                       Dodecylbenzene sulfonic acid                                                                       16                                                       Diethylene triamine   4                                                       Water                26                                                       ______________________________________                                    

This product is an effective emulsion breaker for emulsions produced inthe Glendive field of Montana and is particularly useful as asynergistic component when combined with other aqueous TFSA compositionssuch as described in my co-pending application Ser. No. 082,349, filedOct. 5, 1979, entitled Micellar Solutions of Thin Film Spreading AgentsComprising A Polyether Polyol.

EXAMPLE B

    ______________________________________                                                           Wt. %                                                      ______________________________________                                        Product of Example III                                                                             25                                                       Xylene                8                                                       Sodium salt of p-nonylphenoxy-                                                pentaethoxy sulfuric acid                                                                          15                                                       Isopropanol          31                                                       Methanol              6                                                       Water                15                                                       ______________________________________                                    

This is a solution of very low pour point which is suitable for use as ademulsifier in oil fields where ambient temperatures are well belowfreezing.

EXAMPLE C

    ______________________________________                                                              Wt. %                                                   ______________________________________                                        Product of Example III  31.3                                                  Isopropanol             31.2                                                  Ammonium, nonylphenoxyethoxy sulfate                                                                  15.6                                                  Sodium acetate          0.2                                                   Water                   21.7                                                  ______________________________________                                    

Among procedures which have been found useful in selecting effectivemicellar TFSA solutions for this use, one involves a determination ofoil displacement efficiency from prepared oil-containing rock cores inequipment described below. A tube of glass or transparentpolymethacrylate ester, having an inside diameter of about 3.5 cm (11/2in.) and a length of about 45 cm (18 in.), is fitted with inletconnections and appropriate valves at each end. The tube is mountedvertically on a rack in an air bath equipped with a fan, heater andthermostat which allows selection and maintenance of temperatures in therange of between about 25°-130° C.

To select an effective micellar TFSA solution for use in a given oilformation, samples of the oil, of the producing rock formation and ofthe water to be used in the flooding operation were obtained. Theformation rock is extracted with toluene to remove oil, is dried and isthen ground in a ball mill to the point where a large percentage passesa 40 mesh sieve. The fraction between 60 and 100 mesh in size isretained. The tube described above is removed from the air bath, openedand, after insertion of a glass wool retainer at the lower end, ispacked with the ground formation rock. The tube is tapped gently fromtime-to-time during filling to ensure close packing and is visuallyinspected to assure absence of voids.

The tube is then returned to the air bath, connected to the inlettubing, the temperature is adjusted to the oil formation temperature andwater representative of that produced from the formation is admittedslowly through the bottom line from a calibrated reservoir in an amountjust sufficient to fill the packed rock plug in the tube. This volume isdetermined from the calibrations and is referred to as the "porevolume", being that voluem of water just sufficient to fill the pores orinterstices of the packed plug rock.

The upper line to the reservoir is then connected to a calibratedreservoir containing the oil representing that from the formation to beflooded. By proper manipulation of valves, the line is filled with oilwhich is then slowly pumped into the core from the reservoir after thelower valve is opened to allow displacement of the formation water.

As breakthrough of oil at the bottom is noted, pumping is stopped andthe volume of oil introduced into the sand is determined from thereservoir readings. This is referred to as the voluem of oil in place.The tube of sand containing oil is then left in the air bath at thetemperature of the formation for a period of three days to allowestablishment of equilibrium between the ground formation rock and theoil with respect to adsorption of oil constituents on the rock andlowering of interfacial tension. The time allowed for equilibrium may bevaried widely. At higher temperatures, the time required to reachequilibrium is probably reduced. Usually, for comparative tests, threedays are allowed to age the oil-rock plug. Results with this procedureclosely simulate work with actual cores of oil-bearing rock.

The oil and water samples used for test purposes are preferably takenunder an inert gas such as high purity nitrogen, and are maintained outof contact with air during all miniuplations in order to preventoxidation of the oil and concomitant introduction of spurious polar,surface-active constituents in the oil. At this point, the rock-oilsystem simulates the original oil formation before primary productionoil has commenced and well before any secondary waterflood operation.

The upper inlet line to the tube is now connected to the sample of waterused in the flooding of the oil formation and, by means of a syringepump or similar very small volume positive displacement pump, the wateris pumped into the sand body from the top to displace fluids out of thebottom tubing connection into a calibrated receiver. The pumping rate isadjusted to one simulating the rate of flood water advance in an actualoperation, which is usually in a range of 1 to 50 cm per day. Pumping ismaintained at this rate until two pore volumes of water have been pumpedthrough the sand.

The volumes of fluids collected in the receiver are measured and therelative amount of oil and water displaced from the rock sample aredetermined and recorded. Of special interest is the volume of oildisplaced as a fraction of the original pore volume. This informationmay be viewed as an indication of the approximate percentage of oiloriginally in place which is produced by natural water drive followingdrilling of a well into the rock formation followed by the primary phaseof field production carried to the approximate economic limit.

Following this step, one to three additional pore volumes of watercontaining the TFSA micellar solution to be tested are pumped slowlythrough the plug and the volumes of additional oil and water displacedare determined. Typically, where such an initial "slug" of micellar TFSAsolution is introduced, it may be contained in a volume of fluid rangingfrom 1% to 100% of the pore volume, but most frequently it will be in aslug volume of 10% to 50% of pore volume.

After this final displacement step, the produced oil and water are againmeasured. By comparing the amount of oil produced by this additionalinjection of water containing, or preceded by a solution, of micellarTFSA solution with the amount produced when the same volume of watercontaining no TFSA solution is injected, one can evaluate theeffectiveness of the particular micellar TFSA solution used forenhancing the recovery of additional oil over and above that obtained byordinary waterflooding.

Generally, six or more sand columns of the kind described above aremounted in the heated air bath. Test of a given micellar TFSA solutionis then run in triplicate, using identical conditions andconcentrations, simultaneously with three blank tests run similarly butwithout addition of micellar TFSA solution to the water.

The composition of Example C was tested by this procedure with thefollowing conditions:

    ______________________________________                                        Oil          East Texas Field                                                              API Gravity approximately 40.4                                   Water        Mixed water used in flood operations                             Airbath Temperature                                                                        150° F. (Same as formation temperature)                   ______________________________________                                    

Oil was displaced by pumping two pore volumes of water into the sand.After measuring the volumes of oil and water produced through the bottomline, a further 0.2 pore volumes of water containing 3,500 ppm of thecomposition of Example C was injected followed by 2.8 volumes of watercontaining 200 ppm of the composition of Example C. Measurement of thevolumes of oil and water produced were read after each 0.2 pore volumesof water was injected.

Results of this test at the points of 2,3 and 5 pore volumes of injectedwater are given in the table below wherein averages of three duplicatedeterminations are presented.

    ______________________________________                                        Oil Recovery as % of                                                          Oil in Place                                                                  Pore                                                                          Volumes           Composition of                                                                             Ratio of Increment                             (P.V.)            Example C    of Oil Production                              of                Added to Water                                                                             After Initial 2                                Water  No Chemical                                                                              after Initial                                                                              P.V. Chemical/                                 Injected                                                                             Addition   2 P.V. of Water                                                                            No Chemical                                    ______________________________________                                        2      40.1       40.1         --                                             3      43.2       46.2         2.0                                            5      46.0       50.0         1.68                                           ______________________________________                                    

Use of the composition of Example C in the amounts given above resultedin the production of 100% more oil from injection of one incrementalpore volume of water than was produced by water injection alone and gave68% more oil after three incremental pore volumes of treated waterinjection.

Although the invention has been described in terms of specifiedembodiments which are set forth in detail, it should be understood thatthis is by illustration only and that the invention is not necessarilylimited thereto, since alternative embodiments and operating techniqueswill become apparent to those skilled in the art in view of thedisclosure. Accordingly, modifications are contemplated which can bemade without departing from the spirit of the described invention.

What is claimed and desired to be secured by Letters Patent is:
 1. Ahomogeneous thin film spreading agent solution, comprising: (1) frombetween about 5% to about 75% by weight of a polyepoxide condensate ofat least one of: (a) a polyalkylene oxide adduct of a fusible,water-insoluble organic aromatic hydrocarbon solvent-soluble syntheticresin, wherein said resin has from between about 4 to about 15 phenolicgroups and is an alkyl or cycloaliphatic substituted phenol-aldehydecondensate of an ortho- or para-substituted phenol and an aldehyde, saidcondensate resin being thereafter further condensed with an alkyleneoxide containing less than about five carbon atoms in an amount equal toat least one mole of alkylene oxide per phenolic moiety of said resin,the weight ratio of oxide to condensation product in a solvent-freestate being between about 1-to-10 and about 10-to-1; and (b) a polyetherpolyol having the formula: ##STR6## wherein: A is an alkylene oxidegroup, --C_(i) H_(2i) O--;O is oxygen; i is a positive integer from 2 toabout 10; j is a positive integer no greater than about 100; k is apositive integer no greater than about 100; N is nitrogen; R¹ is one ofhydrogen, a monovalent hydrocarbon group containing less than about C₁₁,or [A_(L) H]; L is a positive integer no greater than about 100; R is ahydrocarbon moietyy of a polyol, a primary or secondary amine, a primaryor secondary polyamine, a primary or secondary amino alcohol, andhydrogen; and m+n is no greater than about 4 when R is other thanhydrogen and one of m and n is zero and the other is unity when R ishydrogen, said polyepoxide being selected from the group consisting ofthe diglycidyl ether of dihydroxyphenyl-methyl methane and the lowerpolymers thereof, diisobutenyl dioxide, polyepoxypolyglycerols,epoxidized linseed oil and epoxidized polybutadiene,said condensate, atabout 25° C.: (A) having a solubility in water and isooctane of lessthan about 1%, by volume; (B) having a solubility parameter from betweenabout 6.8 and about 8.5; and (C) spreading at the interface betweenwhite, refined mineral oil and distilled water to form a film having acalculated thickness no greater than about 20 Angstroms, at a spreadingpressure of about 16 dynes per cm; (2) from about 2% and about 30% byweight of a hydrotropic agent having one of the formulas:

    X--Z                                                       (A)

wherein X is an alkyl, alicyclic, aromatic, alkylalicyclic, alkylaryl,arylalkyl, alicyclicalkyl, heterocyclic or substituted heterocyclicradical having 2 to 13 carbon atoms; and wherein Z is one of:

    --OH; ##STR7##

    --CHO; ##STR8##

    --COOH; and --OCH.sub.3 ;

and U and V are hydrogen or hydrocarbon substituents,

    X--Y--R--(Z).sub.n,                                        (B)

wherein: Z is one of

    --OH; ##STR9##

    --CHO; ##STR10##

    --COOH; and --OCH.sub.3 ;

X is an alkyl, alicyclic, aromatic, alkylalicyclic, alkylaryl,arylalkyl, alicyclicalkyl, heterocyclic or substituted heterocyclicradical having 2 to 12 carbon atoms; R is a member selected from theclass consisting of,

    --CH.sub.2 --, --C.sub.2 H.sub.4 --, C.sub.3 H.sub.5 ═, --C.sub.3 H.sub.6 --, and --C.sub.2 H.sub.4 --O--C.sub.2 H.sub.4 --;

n is either a one or two integer, the integer dependent upon theselection of R; Y is a member selected from the class consisting of:##STR11##

    --O--, and --S--;

and U and V are hydrogen or hydrocarbon substituents;(3) from betweenabout 2% and about 30% by weight of an amphipathic agent having at leastone radical having from between about 10 and about 64 carbon atoms permolecule; and (4) from between about 15% and about 90% by weight, water.2. The composition of claim 1 wherein the polyepoxide is: ##STR12##where n is zero or a positive integer of less than about
 6. 3. Thecomposition of claim 1 wherein the hydrotropic agent is an alcohol. 4.The composition of claim 1 wherein the hydrotropic agent is an aldehyde.5. The composition of claim 1 wherein the hydrotropic agent is asemi-polar oxygen-containing compound capable of forming hydrogen bonds.6. The composition of claim 1 wherein the hydrotropic agent is an amine.7. The composition of claim 1 wherein the hydrotropic agent is a carboxyamide.
 8. The composition of claim 1 wherein the hydrotropic agent is aphenolate.
 9. The composition of claim 1 wherein the amphipathic agentis a hydrophobic hydrocarbon residue-containing composition where thehydrocarbon residue is aliphatic, alkylalicyclic, aromatic, arylalkyl oralkylaromatic.
 10. The composition of claim 1 wherein the amphipathicagent contains an uninterrupted chain of from between about 10 and about22 carbons.
 11. The composition of claim 1 wherein the amphipathic agentis an anion-active soap.
 12. The composition of claim 1 wherein theamphipathic agent comprises ammonium lauryl sulfonate.
 13. Thecomposition of claim 1 wherein the amphipathic agent comprises mahoganyor green sulfonates of petroleum, petroleum fractions, or petroleumextracts.
 14. The composition of claim 1 wherein the amphipathic agentcomprises dodecylbenzene sulfonate.
 15. The composition of claim 1wherein the amphipathic agent comprises sodium naphthenate.
 16. Thecomposition of claim 1 wherein the amphipathic agent comprises cetylpyridinium chloride.
 17. The composition of claim 1 wherein theamphipathic agent comprises trimethyl-heptadecyl ammonium chloride. 18.The composition of claim 1 wherein the amphipathic agent comprisesoctadecylamine acetate.
 19. The composition of claim 1 wherein theamphipathic agent comprises an oxyethylated alkylphenol.
 20. Thecomposition of claim 1 wherein the amphipathic agent comprises analcohol ether of a polyethylene glycol.
 21. The composition of claim 1wherein the amphipathic agent is anionic.
 22. The composition of claim 1wherein the amphipathic agent is cathionic.
 23. The composition of claim1 wherein the amphipathic agent is nonionic.
 24. A homogeneous micellarthin film spreading agent solution, comprising: (1) from between about5% and about 75% by weight of a polyepoxide condensate of at least oneof: (a) a polyalkylene oxide adduct of a fusible, water-insolubleorganic aromatic hydrocarbon solvent-soluble synthetic resin, whereinsaid resin has from between about 4 to about 15 phenolic groups and isan alkyl or cycloaliphatic substituted phenol-aldehyde condensate of anortho- or para-substituted phenol and an aldehyde, said condensate resinbeing thereafter further condensed with an alkylene oxide containingless than about five carbon atoms in an amount equal to at least onemole of alkylene oxide per phenolic moiety of said resin, the weightratio of oxide to condensation product in a solvent-free state beingbetween about 1-to-10 and about 10-to-1; and (b) a polyether polyolderived from the reaction of an alkylene oxide containing less thanabout 10 carbon atoms with a member of the group consisting of polyols,amines, polyamines and amino alcohols containing from about 2 to about10 active hydrogen groups capable of reaction with alkylene oxides, saidpolyether polyol having an average molecular weight of about 15,000 orless, said member having 18 or less carbon atoms wherein saidpolyepoxide is selected from the group consisting of the diglycidylether of dihydroxyphenyl-methyl methane and the lower polymers thereof,diisobutenyl dioxide, polyepoxypolyglycerols, epoxidized linseed oil andepoxidized polybutadiene, said condensate, at about 25° C.: (A) having asolubility in water and issoctane of less than about 1%, by volume; (B)having a solubility parameter from between about 6.8 and about 8.5; and(C) spreading at the interface between white, refined mineral oil anddistilled water to form a film having a calculated thickness no greaterthan about 20 Angstroms, at a spreading pressure of about 16 dynes percm; (2) from between about 2% and about 30% by weight of a hydrotropicagent comprising a semi-polar hydrogen bond forming compound containingat least one of oxygen, nitrogen and sulfur and from between about 2 andabout 12 carbon atoms; (3) from between about 2% and about 30% by weightof an amphipathic agent having at least one radical having from betweenabout 10 and about 64 carbon atoms per molecule; and (4) from betweenabout 15% and about 90% by weight, water.
 25. The composition of claim24 wherein the solubility parameter at about 25° C. of the polyepoxidecondensate is from between about 7.1 and about 7.9.
 26. The compositionof claim 24 wherein the hydrotropic agent is an alcohol.
 27. Thecomposition of claim 24 wherein the hydrotropic agent is an aldehyde.28. The composition of claim 24 wherein the hydrotropic agent is asemi-polar oxygen-containing compound capable of forming hydrogen bonds.29. The composition of claim 24 wherein the hydrotropic agent is anamine.
 30. The composition of claim 24 wherein the hydrotropic agent isa carboxy amide.
 31. The composition of claim 24 wherein the hydrotropicagent is a phenolate.
 32. The composition of claim 24 wherein theamphipathic agent is a hydrophobic hydrocarbon residue-containingcomposition where the hydrocarbon residue is aliphatic, alkylalicyclic,aromatic, aryalkyl or alkylaromatic.
 33. The composition of claim 24wherein the amphiphatic agent contains an uninterrupted chain of frombetween about 10 and about 22 carbons.
 34. The composition of claim 24wherein the amphipathic agent is an anion-active soap.
 35. Thecomposition of claim 24 wherein the amphipathic agent comprises ammoniumlauryl sulfonate.
 36. The composition of claim 24 wherein theamphipathic agent comprises mahogany or green sulfonates of petroleum,petroleum fractions, or petroleum extracts.
 37. The composition of claim24 wherein the amphipathic agent comprises dodecylbenzene sulfonate. 38.The composition of claim 24 wherein the amphipathic agent comprisessodium naphthenate.
 39. The composition of claim 24 wherein theamphipathic agent comprises cetyl pyridinium chloride.
 40. Thecomposition of claim 24 wherein the amphipathic agent comprisestrimethyl-heptadecyl ammonium chloride.
 41. The composition of claim 24wherein the amphipathic agent comprises octadecylamine acetate.
 42. Thecomposition of claim 24 wherein the amphipathic agent comprises anoxyethylated alkylphenol.
 43. The composition of claim 24 wherein theamphipathic agent comprises an alcohol ether of a polyethlene glycol.44. The composition of claim 24 wherein the amphipathic agent isanionic.
 45. The composition of claim 24 wherein the amphipathic agentis cationic.
 46. The composition of claim 24 wherein the amphipathicagent is nonionic.